JezC - the second (and laST) H5C1 build

[JezC]

So, I seem to have acquired a second H5C1 board (shortly before the rest of the stock disappeared) ;)

Having had a few spare minutes at lunch time, I've stared the build...

Progress so far: I've fitted
ROM jumper
SIMM socket
VGA connector
read Reset switch
Flashy Clock link (for now there's no Flashy Clock to fit...)
Link on real-time clock (will be fitted later - if I can get it to boot...)
Oscillator
Keyboard jumper pad

I'll get the floppy lead fitted a bit later (probably after I've completed a minimal build & checked it boots to the desktop using chips borrowed from the other H5C1 with a floppy access issue).

Next is to check what else I need to fit for it to boot...hopefully more progress later tonight!

[exxos]

We need images or it didn't happen! :lol: :chairsmack:

[JezC]

We need images or it didn't happen! :lol: :chairsmack:

Well, I was planning to wait until I'd got it to boot to the desktop...but since you ask...

IMG_20240411_142131904.jpg

[JezC]

Keyboard keying pin removed, various jumpers fitted so next will be fitting the chips from H5C1 #1 and a test to see if she boots!

[exxos]

Keyboard keying pin removed, various jumpers fitted so next will be fitting the chips from H5C1 #1 and a test to see if she boots!

:excited: :excited: :excited: :excited:

[JezC]

Keyboard keying pin removed, various jumpers fitted so next will be fitting the chips from H5C1 #1 and a test to see if she boots!

:excited: :excited: :excited: :excited:

:) as long as it's not

:fire1:

I'll be happy!

[JezC]

Well, all chips plugged in & it powers up....to a solid white screen, darn. :(

I'll go through the fault-finding steps (probably tomorrow) as best I can - no 'scope at home at the moment, so it might have to just be the Saleae logic analyser for now.

I'm suspecting it could be a ROM fault but I'll check the key signals after power-up and go from there...

:sigh:

[exxos]

@JezC You sure you got the ROM jumper in the right place and not trying to boot from TOS206 ?

Also don't forget the OSC needs that 470 on it else you can have reset issues..

[JezC]

I've tried it with and without the jumper fitted with no difference (but I'll double-check the soldering tomorrow - just in case!)

I've not fitted the resistor yet so I'll see if I have anything suitable at home...if not, that will have to wait until Monday when I'm in the office & can raid the surface mount resistor samples!

More updates when I make some progress...

[exxos]

I've not fitted the resistor yet so I'll see if I have anything suitable at home...if not, that will have to wait until Monday when I'm in the office & can raid the surface mount resistor samples!

You could tag a normal resistor across the back of the motherboard.. Just not ideal to leave it that way.

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